Automatic magnetic circuit-breaker.



W. M. SCOTT.

AUTOMATIC MAGNETIC CIRCUIT BEBAKER.

' A APPLICATION FILED JAN. 19, 1907. 940,647 PatentedNov. 16, 1909. 2 SHEETS-#SHEET 1.

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W. M. SCTT. AUTOMATIGMAGNETIG CIRCUIT BREAKER.

APPLICATION FILED JAN. 19, 1907.

Patented Nov. 16, 1909,

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UNITED sTATas y PATENT onirica.

WILLIAM M. SCOTT, OF PHILADELPHIA, PENNSYLVANIA., ASSIGNOR TO THE CUTTER ELECTRICAL AND MANUFACTURING COMPANY, A CORPORATION F NEW JERSEY.

limcioiuATIc MAGNETIC cIRcUIT-BREAKER.

Specification of Letters Patent.

Patented Nov. 16,v 1909.

Application filed January 19, 1907. Serial No. 353,047.

To all whom it may concern:

Be it known that I, WILLIAM M. SCOTT, a

1 ating handle.

4 same.

Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a new and useful Automatic Magnetic Circuit- Breaker, of which the following is a specification.

My invention relates to electrical switches and more particularly to automatic switches or circuit breakers, and particularly elec trical switches or circuit breakers suitable for handling very heavy currents, as, for example, hundreds or thousands of amperes.

My invention resides in eilicient means for operating or controlling a movable switch contact suitable for carrying very heavy currents, such means comprising force-multiplying mechanism which enables an operator to efectually and easily close the switch by a lmoderate sweep'of the oper- By my invention, the operating handle protrudes from the base or switchboard a small dist-ance only when considering the size of switch contact to be operated.

My hereinafter described and pointed out in the claims.

For an illustration of a form my invention may take reference is to be had to the accompanying drawing, in which:

Figure 1 is a side elevation of an automatic circuit breaker embodying my invention. Fig. 1a is a fragmentary viefw of the side elevation shown in Fig. 1, paits being broken away for the sake of clearnss. Fig. 2 is a side elevation of the cam member. Fig. 3 vis a front elevation of the same. Fig. 4 is a side elevation of the tripping member. Fig. 5 is a front elevation of the Fig. 6 is a side elevation of the latch. Fig. 7 is a front elevation of the same.

Referring to Fig. 1, 1 and 2 represent terminal blocks of copper secured upon the front of the base or switchboard 3, of insulating material, by the nuts 4 and 5 respectivelyengaging upon screwthreaded studs communicating with said terminal blocks. The movable contact member 6 is of the laminated type secured upon but insulated from the arm 7, pivoted at 8 to the bracket 9 secured upon the base.` Secured upon the upper main contact 1 is a metallic invention resides kalsof-in other :featuresV shunt contact piece 10 with which cooperates the'movable metallic shunt contact plece 11 supported by the spring 12 upon the arm 7. Also secured upon and in electrical communication with the terminal block 1 .is the bracket 13 to which the stationary carbon contact 14 is provided at 15. The movable shunt carbon 16 'coperates with the carbon 14 and is supported upon a spring 17 carried by the arm Pivoted in the arm 19, which is adapted to engage the cam surface 20 of the cam member `21, pivoted in the bracket 9 at 22. The cam surface 20, at the region where it is engagedby the roller 19 when the parts are in open circuit position, has a relatively great pitch so that the parts move quickly fora given angular movement toward circuit closing position. When the laminated member 6 engages the main contact blocks the cam surface 20 changes quiteV abruptly into a part havinl very slight pitch, whereby with considera le remaining angular movement of the member 21, slight travel of the laminated member 6 is effected,

but with very considerably increased force.

They cam member 21 extends downwardly beyond the pivot 22 in the separated wings 23 and 24. In each of the wings 23 and 24, is disposed a cam slot 25. The shape of the slot and its arrangement with respect to the cam member 21, is such also as to have in effect a cam surface of slight pitch especially near the end of the circuit closing movement, thus exerting a powerful force upon the cam member 21 duringthe period of cramping ther laminated member 6 against the main contact terminals 1 and 2. In eachof the cam slots 25 is a roller 26 mounted upon pin 27, the pin 27 being secured at its ends in-the ears 28, secured to and extending' downwardly from the lever 29, pivoted to the bracket 9-at 8. Pivoted at 8 also is the operators lever 30, having the handle 30', and having the upward extension 31 to which is secured one end of the helical spring 32 whose other end is secured to the lever 29, the spring 32 being under tension, as shown in Fig'. 1, when the parts are in circuit closing position, and whenever the levers 29 and 30 are latched together. Secured to Ithe operators lever 30 is a member 33 to which is pivoted, at 34, the latch 35, which is bifurcated, as'shown in Fig. 7 and carries at its outer end an anti-friction roller 36. The

7, at 18, the roller hook of the llatch 35 is adapted to engage and hold the roller 37, mounted upon the pin 27 and disposed between the wings 23 and 24 ofthe cam member 21.

A tripping member 38 is pivoted in the bracket 9 at 22 independently of the cam member 21. This tripping member has a downward extension 39, whose surface 40 is adapted to engage the roller 36 on the latch 35 to actuate said latch. It 'also 'has a shorterextension 41, which lies in the path of travel of the lever 42, pivoted to the' frame at. 43 and having the extensions 44 and 45. The extension 44 is adapted to be engaged by the projection 46 upon the armature 47, pivoted at 48 and adapted to normally rest 1upon the non-magnetic sto 49 between the cores 50 and 51 of two coi s 52 and 53 respectively. The third coil 54 has for its core the pivotally mounted cross connecting member between' the two similar armatures 47. And the extension 45, of the lever 42, lies in the path of the pivoted armature 55- ot' the overload tripping magnet which is pivot-ed on an axis normal to the front` faceoi the switchboard 3.

The cam surface 20 of the cam member 21 is of such shape 'that with the parts in open circuit position, the subsequent clockwise rotationof the cam member 2ly about its pivot 22, forces the roller 19 and, therefore, the arm 7 very rapidlyV toward circuit closing ositionduring the initial movement `Wl1en t elaminated bridging member 6 has come into engagement 'with the terminal blocksl' and 2, the vfirst real mechanical resistance 1s oii'ered and :from that time on to full circuit closing position, the eatest amount of force must exerted. uring such closing period, the part ofthey cam surface 20 which isengaged by the roller 19, increases in distance from the pivot 22 by'v relatively slighter increments than in the earlier part of the movement. This permits, as stated, a free and rapid closing of the movable contact member t3 during the first part of the closing movement, and for the remainder of the closing movement the movement'ot' the member 6 is very slight, the cam member 21 exerting, however, greatly increased force to cram the laminated contact member 6 into fullcircuit closing positionn The rollers 26, carried by the lever 29, engage in the cam slots 25 olthe two Wings 22 and 24 of the cam member 21. The cam slot 25 is of such shape also that, near the end of the closing movement very great force is exerted to rotate the cam member 21 in a clockwise direction, the lever 29 moving a considerably greater distance than the cam member 21.

With the parts. in the open circuitposi- I tion, the operator raises the-lever 30, until the latch 35 en ages the roller 37, carried by the lever'29, w ich lever in the open circuit position, is elevated above the position shown in Fig. 1, with the rollers 26 at or approximate the upper ends of the cam slots 25. With the handle 30 thus locked to the lever 29, the o erator depresses the lever30 causing relatively great angular movement in avclockwise direction of the camgniember 21 aboutl the pivot 22 until near the end of the circuit closing movement when the cam member 21' movesl more slowly and exerts greater force. Vhen the position showuin Fig, 1 has been reached the switch is locked in circuit closing position because the strain exerted by the cam 1nember2l against the pin 27, which is lockedby latch 35 to lever 30, is in such direction that the parts cannot move to open position.

' Assuming the circuit breaker closed, as shown, either when by overload the armature '55 is actuated, or'the armature 47 lis actuated, the lever 42 is rotated in ak clockwise direction about its pivot 43 striking the extension 41 of the tripping member 38 whose longer extension 39 then engages by its surface 40 againstl the rollerv 36 carried by the latch 3 5, tilting that latch ina clockwise direction about its pivot 34 to release the roller 37. In other words, upon `the actuation of either of the electro-responsive means, the latch 35 is actuated and the lever 29 released from the lever 30. Then, due rto the tension of the spring 32, as well as to the spring effect exerted by the laminated member 6, and gravity, the lever 29 rises.

y29, rotates in a counter-clockwise direction,

so that first the laminated bridging member separates from the main contact-s l and 2, later the metallic shunt Contact piece 11 separates from the shunt contact piece 10, and finally, the carbon 16 separates from the carbon 14. If, upon attempting to close the circuit breaker, an abnormal circuit condi'- tion exists, either an abnormal condition of.

overload or potential variation, after having raised the handle 30 to lock it to the lever 29 and depressing the same in closing movement, as .soon as iii-st substantial con-l tact is made, either one or the other of the electro-1esponsive means will operate to tilt the`latch 35, to unlock member 21 from the 4lever 29. So itis that the operator is robbed of control if there exists an 'abnormal cirp cuit condition, andthe parts cannotbe moved` to or locked in the full circuit closing position.

What Iclaim is: l. In an electrical switch, the combination with a fixed terminal block, of a movable laminated contact member, a cam member for cramping said'laminated contact mem-` ber against said terminal block, a vsecond cam member for actuatingk said cam member,

the pitches of the portions. of the surfacesv of said cam members, active duringV said block, the pitch of the surface of said cammember, active during cramping movement, being slight, a second cam member for actuating member in normal position, the locking strain being transmitted through saidcam members. i y

3. In an'electrical switch, the combination with a movable contact member, of a cam member for actuating the same, amember engaging said cam member to actuate the saine by cam action, an actuator, and means for locking said actuator to said member. y

4. In an electrical switch, the combination with a movable contact member, of a cam member for actuating the same, a member for "actuating said cam member by .pin and slot engagement, an actuator, and a latch for locking said actuator to said member, whereby said camv member maybe actuated to movel said contact member to normal position, said member when latched to said actuator constituting means for restraining said contact member in normal position.

5. Iii an electrical switch,`the combination with a movable contact member, of a cam member for actuating the same, a lever engaging with said cam member ,to actuate the.

same by cam action, an actuatorlever, and

means for locking said levers together,"

whereby saidactuator lever may move said contact member to normal position.

6.- In an electrical switch, the combination with a movable contact, member, of an independent cam member for actuating the same, a cam slot in said cam member, a lever engaging in saidcami slot to actuate said camY member, an actuator lever, and a latch for locking-,said actuator lever to said lever, whereby said levers operate as a unit to actuate said cam me ber and serve as means for restraining said ontact member in normal position.

7. In an electrical switch, the combination with a movable contact member,'of a cam member for actuating the'saine, and levers concentrically pivoted and latched together for actuating said cam member and restrain,- ing said movable contact member in normal position.

8. An automatic circuit breaker comprising a movable contact member, ya cam meinber, :for actuating said contact member, `a member engaging said cam member to actuate the same by cam action, an actuator, a

latch for connecting said actuator and said said cam member, said cam members' serving to restrain said laminated contact 4tween said levers.

. an actuator member, and electro-responsive means for actuating said latch upon.moveinent of said Contact member to normal position during the existence or, continuance of predetermined electrical conditions.

9. An automatic circuit breaker comprising a movable contact member, a cam member for actuating the sa-me,'a lever engaging said cam member to actuate the same by cam action, an actuator lever, a latch connecting said levers, whereby said contact memberv is locked in normal position, and electro-responsive means for actuating said latch.

10. In an'electrical switch, the combination `with a movable contact member, of means for actuating the same comprising pivoted levers latche'd together, one of said" as a lock for said ,movable and a spring acting belevei's servin Contact mem er,

11. In an electrical switch, the combination with a movable contact member, of

means for actuating said contact member 'comprising concentrically pivoted levers latched together, a spring acting between said levers, and a vcam intervening between said latclied levers' and said contact member.

12. In an electrical switch, the combination with a movable contact member, of

pivoted lever for operating the same and serving as a lock, an'actuator, a'latch conv necting said actuator and lever, and a spring acting between said lever and said actuator.

13. In an electrical. switch, the combination with a movable'contactmember, of a cam member engaging ,the same, a pivoted lever for operating said-cam member, an actuator, a latch connecting said pivoted lever and actuator, and a spring acting between -*said lever and said actuator.

lcam meniber.- engaging the same, apivoted lever engagin said cam member, 4an actuator, a `latc connecting said lever and actuator, and a spring joining said lever and actuator. Y

i 16. In an electrical switch, the combination with a movable cont-'act member, of

cam members for operating the same, a pivv oted lever for operating said cam members, i i

lpivoted concentrically with said lever, a latc connecting said lever and ac-y tuator, and a spring joining said lever andv actuator. I v 17. 4In an electrical'switch, the combination with a movable contact member, of a pivoted lever for actuating saidj contact.

' sive means` for actuati member, an actuator lpivoted. concentrically 1 with said lever, a latch-connecting said lever and actuator, and a spring connecting said lever and actuator and disposed to se arate said lever and actuator when'unlatche 18. In an electrical switch,'the combination with a movable contact member, ofa cam member for actuating the same, a pivoted lever for engaging said cam member, an actuator, anda latch connecting said actuator and lever.

19. In an electrical switch, the combination with a movable contact member, of a cam member for actuating the same, a pivoted lever for engaging said cam member, an actuator, a latch connecting said actuator and lever, and a spring vjoining said lever .tion with a movable contact member, of a cam member for actuating the same, and pivoted levers latched together for actuating said cam member, one of said levers serving as a lock for said cam member for restraining said contact member in normal.y

position;

22. In an automatic circuit breaker of the non-closable type, the combination with a movable contact member, of a member for operating the same, a pivoted lever engaging saidV operating. member and serving to lock the same, a pivoted actuator, a latch locking said lever and actuator, together, and electro-responsive means for actuating said latch to disconnect said lever from said actuator,

23. In an automatic circuit breaker of the non-closable type, thecombination with a movable contact member, of means' for actuating* the same com rising a pivoted lever, a pivoted actuator, a atch lockmg said lever and actuator together, said lever serving' as the lock for restraining said contact member in normal position, andl electro-responsive means for actuating said latch.

24. In an automatic circuit breaker of the non-closable type, the combination with a movable contact member, of a cam mem- Iber for operating the same, a lever for operatin said cammember and serving as a lock fort e same, an actuator, aflateh connecting said lever and actuator, and electro-responsai'd latch.

25. In an 'automatic circuit breaker of the .non'closable type, the combination with a movable contact member, cfa cam' member for actuating the'same, a single latch, va

: i l 4 1 pivoted lever engaging said cam member, a pivoted actuator; said' lever and actuator connected by said latch, 4and electro-respon-y pivoted operating member therefor, ay lever for actuating said operating member, an.

actuator, a latch connecting said lever and actuator, and a latch actuatlng member pivoted concentrically with said operating 'I member.

28. In an electrical switch, the combina'- tion with a movable contact member, of a cam member for operating the same, a lever for actuating said cam member, an actuator,

' a latch connecting said lever and actuator,

sol

and a latch actuating member pivoted con-v centrically with said cam member.

29. In an electrical switch, the combination with a movable contact member, of a. y

cam member for operating the same, a lever Afor operating said cam member by cam action and for lookin said cam member, an actuator, and a latcIx and actuator.

30. 4In an electrical switch, the combination with a movable contact member, of a cam-member for operatinglthe same, a lever connecting said lever vio'o for operating said cam member and serving i asa lock for the same, an actuatora spring and a latch connectingfsaid lever and actuator, andmeans ,for actuatin said latch to release said lever to the in luence of said spring, whereby. Vsaid cam member 'is un' locked. ,y

31. In an electrical switch, a. hook latch, a latch actuating member, and a roller pivoted in said hook latch and adapted to be engaged by said latch actuating1 member.

32. I n an electrical switch, e combinat1on with a movable contact member, of

means for operating the same havingl a slot,

a lever, a member carried by said lever and engaging in said slot and serving to lock said operating'. means, a sprin enga said lever, a latch engaging sai lever, an means for actuating said latch to release said lever to the influence of said sprin, whereby said operating means are unlocke In testimony whereof I have hereunto affixed my signature in the presence ofthe two subscribing witnesses. l

WILLIAM M. SCOTT.

Witnesses:

DANL WEBSTER, Jr., ANNA E. STnINBoeK. 

